Republic of Ireland boss Martin O'Neill was handed a boost when John O'Shea and James McClean both boarded the plane for Vienna.

The vastly-experienced Sunderland defender and the West Brom midfielder had been doubts for Saturday's World Cup qualifier in Austria because of hamstring and back injuries respectively, and the presence of both among the party which left Dublin on Thursday afternoon came as a relief to O'Neill.

However, only 27 of the 28 squad members jetted out with Leeds midfielder Eunan O'Kane having returned to his club for treatment on a groin problem.

A Football Association of Ireland statement said: "Midfielder Eunan O'Kane has returned to his club, Leeds United, due to a groin problem, while John O'Shea and James McClean both took a full part in training at the FAI National Training Centre on Thursday morning.

"The travelling squad to Vienna consisted of 27 players in total, including Dundalk duo Andy Boyle and Daryl Horgan."

McClean in particular could have a key role to play at the Ernst Happel Stadium with O'Neill's attacking options having been reduced significantly by Robbie Keane's retirement from international football and injuries to Shane Long and Daryl Murphy.

The former Derry City man scored twice in last month's 3-1 victory in Moldova, which extended the Republic's positive start to their Group December campaign to seven points from a possible nine.

They currently trail group leaders Serbia only on goal difference and any addition to their total in Austria would leave them in a strong position when hostilities resume in March next year.